#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
int main() {

	int a = 999;
	int b = 666;
	printf("%d\t%d\n", a, b);
	a ^= b;
	b ^= a;
	a ^= b;
	printf("%d\t%d", a, b);

	return 0;
}